1. Field of the Invention
The present invention is directed to an apparatus and to a method for erection and disassembly of a sectional mast assembly. In particular, the present invention is directed to an apparatus and method wherein sections or segments of a mast assembly are sequentially inserted, raised, and installed.
2. Prior Art
A mast or a derrick of a rig, such as a subterranean drilling rig, supports a block and tackle to raise and lower drill hits, drill pipes and other equipment. Drilling rigs can be used for mineral exploration drilling, water well drilling, oil well drilling, and natural gas drilling. When in operation, a mast will often extend up to 200 feet from the ground. Once a drilling project has been completed, the drilling rig is disassembled, transported to the next location, and then reassembled for use. Accordingly, the ability to quickly and efficiently erect and then disassemble a drilling rig is of paramount importance.
Assignee's U.S. Pat. No. 6,594,960 entitled “Method of Folding an Articulating Mast” shows an example of raising or lowering of a mast utilizing a folding gin pole and drawworks.
In some use applications, the space on or adjacent to the rig is at a premium, such as in mountainous locations or off-shore on a marine platform.
In these cases, it would advantageous to be able to install and assemble the drilling mast in sections or segments and to disassemble the mast in sections or segments.
The present invention provides an apparatus and a method for erection and disassembly of a sectional mast assembly which requires minimum equipment sizes, minimum platform area and minimum transport loads.
The present invention also provides an apparatus and a method for erection and disassembly of a sectional mast assembly which minimizes required personnel for erection and disassembly of the sectional mast assembly.
The present invention also provides an apparatus and a method for erection and disassembly of a sectional mast assembly which utilizes power systems existing on a drilling rig.